In a wireless communications system, a user equipment UE (User Equipment) needs to perform various types of measurement related to a downlink channel, including: reference signal received power RSRP (Reference Signal Received Power)/reference signal received quality RSRQ (Reference Signal Received Quality) measurement, channel state information CSI (Channel State Information) measurement, and the like. In the 3rd Generation Partnership Project 3GPP (3rd Generation Partnership Project) Long Term Evolution LTE (Long Term Evolution) Rel 10 protocol, a base station sends a non-zero power channel state information reference signal CSI-RS to a UE within coverage of the base station for CSI measurement; while in the 3GPP LTE Rel 11, that a UE performs CSI-RS RSRP measurement based on a non-zero power CSI-RS is introduced.
The base station configures multiple CSI-RS resources for the UE, including: a non-zero power CSI-RS resource and a zero power CSI-RS resource. When data is transmitted to the UE, REs (Resource Element) that correspond to all the CSI-RS resources configured for the UE by the base station cannot be used for mapping data; therefore, more REs of configured as non-zero power CSI-RS resources or zero power CSI-RS resources indicate fewer REs that can be used for transmitting data, and the spectrum efficiency of data transmission is relatively low.